A proposal to close the Maine Energy Recovery Co. incinerator in downtown Biddeford and send the waste to a landfill in Old Town has died in the state Legislature, leaving the future of a transfer station planned for Westbrook unclear.

On Tuesday, the Maine Senate decided to kill a bill aimed to facilitate the closure of the waste plant by negotiating the transfer of the Juniper Ridge Landfill in Old Town from the state to Casella Waste Systems, which hopes to increase the size of the site to accommodate more municipal waste.

The closure of Maine Energy Recovery Co., owned by Casella, could have led to the start of construction of a long-delayed transfer facility on land owned by Casella in Westbrook. Casella’s history in Westbrook is a long one, as the company has put forth several proposed uses over the last decade for its land, located at 600 County Road, but to date, none of those plans has come to fruition.

State Sen. Thomas Saviello, the chairman of the Environment and Natural Resources Committee, said that while the bill is dead for this session, he “suspected” that it would be submitted in the next legislative session in January 2013.

As part of the recent proposal, Casella would sell Maine Energy Recovery Co. to the city of Biddeford for $7.5 million, and the city would close the incinerator. The waste company would then transport trash to Westbrook for processing, and then to the Juniper Ridge landfill in Old Town for disposal.

In exchange, Casella asked the state to transfer ownership of the Juniper Ridge facility to Casella, which currently operates it, and allow a limited amount of out-of-state waste to be disposed of there.

Both Biddeford Mayor Alan Casavant and Casella’s spokesman, Joseph Fusco, however, have emphasized that there is no set timeline for the proposed sale and closure of the plant.

“I would like to move quickly, but I also want the public to be fully educated on the final proposal and have good public discussion,” Casavant said last week.

Fusco stressed the importance of agreeing to a plan rather than focusing on a specific time goal, adding that things “happen when they happen.”

As for the plans for the Westbrook property, Fusco said last week that there is no timetable for Casella to begin any work on the County Road site, as that work is contingent on the sale of the Biddeford incinerator.

“It’s all part of a pageant of moving parts,” he said.

There is no proposal from Casella before the city of Westbrook. Last week, City Engineer Eric Dudley said that Casella would need to go before the Planning Board for approval before any construction at the site could get under way.

One plan that had been put forward by the company in the past was to use the proposed Westbrook facility to process trash into burnable pellets, which would have then been used as fuel at the Biddeford incinerator. Fusco said that since the new plan calls for the closure of the Biddeford plant, there would be no need to create the burnable pellets.

Fusco added that the plan to close Maine Energy Recovery Co. and possibly construct the Westbrook transfer station did not necessarily hinge on the effort to transfer ownership of the Juniper Ridge landfill.

“I don’t think any one thing is dependent on another,” he said.

Acknowledging that past efforts to close the incinerator have failed, Fusco said many are “optimistic” that these talks will achieve what other discussions have not.